Zero footprint applications are computer applications which require end users to install little, if any, software. Examples include web-based e-mail applications such as Yahoo Mail®, GMail®, and Hotmail®. Zero footprint applications provide advantages for both the application service provider and the end users. End users benefit from a high level of accessibility to the application, such as through the World Wide Web, and ease of use. Application providers are able to control the user interface and can control software updates from the network. These applications offer interactivity and functionality to more users without requiring an install, as well as offering a convenient mechanism for sharing and centralizing data.
Another major driver of zero footprint applications are corporate and government environments, where end users are often prohibited from installing applications to their PCs or laptops. In such environments, the deployment of zero footprint applications is often much simpler compared to traditional applications, which require installation, because the former can be released immediately while the latter typically requires certification and security reviews.
One type of zero footprint applications is geographic information systems. A geographic information system is an information system for capturing, storing, analyzing, managing, and presenting data which is spatially referenced (e.g., linked to a location). Geographic information systems may be used for scientific investigations, resource management, asset management, environmental impact assessment, urban planning, cartography, criminology, geographic history, marketing, and logistics to name a few. For example, a geographic information system might allow emergency planners to calculate emergency response times in the event of a natural disaster or to find wetlands that are in need of protection.
The use of zero footprint applications for geographical information systems presents difficulties. One such difficulty involves creating usable business logic in such a way that it can be shared across applications in a controlled fashion. To date, geographic information systems available in zero footprint environments tend to be simplistic in contrast to their dedicated full-scale counterparts.
As an illustration, FIG. 1 is a block diagram depicting a prior art geographical information system 30. A user 32 is able to access the geographical information system 34 through one or more servers 36. For example, a user 32 may request the display of a map through a zero footprint client, such as a webpage in a web browser. The user request is forwarded to the geographical information system 34 via the one or more servers 36. Upon receiving the request, the geographical information system 34 may access data from a geographic data set stored in one or more data stores 40. This data 38 accessed from the data stores 40 may be the data necessary to generate the graphical map requested by the user 32. Upon receiving the data 38, the geographical information system 34 generates the requested map and transmits the map data to the user 32 via the one or more servers 36 for display in the zero footprint client.
As another illustration, FIG. 2 depicts output of a geographical information system identifying an address on a map 50. This map was accessed from Google® Map Data. A user may request the map 50 depicted in FIG. 2 by entering the address, “121 N. Monroe St., 16354” into an map address dialog box on a web page in a web browser. The request is sent through the World Wide Web to a server where the requested map data is accessed, processed, and provided for viewing by the user on the web page in the web browser.
As yet another illustration, FIG. 3 depicts output of a geographical information system that provides directions for traveling between two points on a map 60. This map was accessed through the Yahoo® Local Maps application. A user may request a map similar to the map 60 depicted in FIG. 3 by entering two addresses in a “Get Map and Directions” dialog box on a web page in a web browser.